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Is homosexuality is the result of genetics

  1. Dec 6, 2003 #1
    If homosexuality is the result of genetics gone wrong then how come their is no other gay animals in the world?
  2. jcsd
  3. Dec 6, 2003 #2
    Re: question

    There are recorded examples of homosexual behavior among a number of animal species.
    Last edited: Dec 6, 2003
  4. Dec 7, 2003 #3
    Do mind giving any examples?
  5. Dec 7, 2003 #4
    Put 2 young male dogs in a pen together. Watch and learn.

  6. Dec 7, 2003 #5
    Of examples I've heard of, there has been observed homosexual activity between: dogs, rats, elephants, rhinocerouses, dolphins, chimpanzees, lions, giraffes, cows, sheeps, gorillas, and a lifelong homosexual relationship between two male ganders, to name just a few off the top of my head.
  7. Dec 7, 2003 #6
    Surely, you can come up with more than that. You left out humans


  8. Dec 7, 2003 #7
    That usually happens out of aggressive behavior or competition of who is the dominant one. Its not driven by a sexual attraction.
  9. Dec 7, 2003 #8
    How do you know?
  10. Dec 8, 2003 #9
    Because there is no intent of actual mating happening its more of mislead aggressiveness
  11. Dec 8, 2003 #10
    I repeat my question.
  12. Dec 8, 2003 #11
    because almost all of the time they get intimate with a leg or stomach and never in the normal spot where mating is always intended.
  13. Dec 8, 2003 #12
    What are you talking about? Even if I were to accept the above claim as true -- and I'm not sure why I should -- what is "the normal spot where mating is always intended"? Are you talking about direct genital-to-genital contact? That doesn't tend to happen even in human homosexual congress. How does one experimentally determine whether sexual attraction is involved? Is it involved between animals in heterosexual congress? How can we tell?
  14. Dec 8, 2003 #13
    I don't know ask a biologist
  15. Dec 9, 2003 #14
    I, also, am confused as to what you consider the "normal" spot. Like I stated, earlier. Put 2 male dogs in a pen and watch. I am not sure if you consider the anus a "normal" spot, but it is as normal as human anal sex.

  16. Dec 9, 2003 #15


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    I've had lots of cats and dogs (among rodents and birds). All the cats have been.. euh.. well, castrated so I have no data on that. The dogs do quite a bit of humping though, I wouldn't say it is homosexual behaviour, just an instinct, like dogs humping a leg.

    I think homosexual behaviour should be defined as the formation of life-partner. Not sure which animals do that, some parrots do, maybe someone has done the research whether all the couples are male-female or some are not?
  17. Dec 9, 2003 #16
    I can understand that a female can have sex with another female and be considered a "bisexual". But if a male has sexual relations with another male - he is a homosexual - whether it is a life partner or not. I guess I don't understand why you think, one has to form a life partner - to be considered a homosexual. That is like saying male and female who have only intercourse are not heterosexual.

  18. Dec 10, 2003 #17
    What I'm trying to get at in this thread is that homosexuality seems to be a psychological thing, meaning that it is a choice, as opposed to gene mix ups.
  19. Dec 10, 2003 #18
    Are you under the impression that genetics has no influence on psychology?
  20. Dec 10, 2003 #19
    Remember, it's not "gene mix-ups" but hormone "mix-ups". Even if homosexuality was a genetic trait (which it isn't) it wouldn't be passed too often methinks ...

    Anyway, you are probably right that this is often the case, but not always or even necessarily usually.
  21. Mar 19, 2007 #20
    Heterosexuality is rare in nature

    Friends let me present a totally different perspective.

    There is hardly any evidence of heterosexuality amongst mammals. And its incidence is only substantial in birds, but almost absent in other species.

    Now before you all jump at me. Let me start by saying that the western concepts of 'homosexual' and 'heterosexual' are quite misleading (for one thing since there is a group 'homosexual' we automatically associate male-male sexuality with that group, whereas it doesn't work that way practically). So let me give you my own definition of heterosexuality.

    In India males don't consider themselves 'heterosexual' (nor homosexual). They are either masculine men or feminine males (third gender). Besides bisexual behaviour is very common.

    Redefinition of Heterosexuality:

    Heterosexuality is used for the following kinds of male-female sex:

    - Sex for reproduction

    - constant/ exclusive sexual desire for opposite sex.

    - A need for sexual bonding between opposite sex.

    Of these only the last two traits form the distinguishing feature of a 'heterosexual'. Sex for reproduction is a drive that may come rarely or intermittently in life and one doesn't need to be a 'heterosexual' for that. E.g. one can be in a relationship with another man but still may have sex for reproduction.

    What I am saying is,........ and I'm saying it after studying wildlife a lot........

    that in nature (except for birds) there is only sex for reproduction. there is no sex for bonding between opposite sex, and male-female sex for purely pleasure is also very rare.

    Esp. in mammals male and female live in separate, non-heterosexual groups (excepts for a few males in some species who may join the female group, either as transgenders or as owner of 'harems'). Males and females meet each other only during the mating season. This meeting/ mating is very short and usually ends when sufficient ejaculation to ensure reproduction is achieved. Soon after that the male (and the female) lose interest in each other. There is no constant sexual desire for each other. And surely there is no emotional bonding like love happening here. Males (and females) don't even look at each other or recognise each other's presence once they get over with it. And the sexual feelings of males is definitely not exclusively towards females. They are very open to, and in fact prefer bisexual behaviour.

    It is not that sexual 'bonding' doesn't exist in mammals. But rather than with the opposite sex, it happens amongst same-sex as is shown by various studies (Please refer to Bagemihl's book "biological exuberances).

    Therefore, same-sex feelings may neither be psychological nor a genetic mix-up but the preferred sexuality of nature.

    Whereas, opposite sex bonding, and an exclusive/ constant sexual desire for women, as displayed by human males is probably neither normal nor natural. It is either 'caused' by something special that humans have, or is purely a result of social mechanisms that condition, train and force people (especially men) to be heterosexual.

    You may jump in to tear me apart, NOW!
  22. Mar 20, 2007 #21
    please, if you make that claim, back it up... seeing as so many studies are constantly being made by scientists trying to understand this complex subject..

    the way I see it, so far, while sexual preference seems to be a product of both, a genetic predisposition is needed (much like genetic predispositions to many mental conditions do not mean 100% that you will have that condition).

    what I take from what we know so far is that we are all born with a genetic predisposition to heterosexuality, homosexuality, or somewhere in the middle. for those who lie in the middle, several experiences in their life could affect them one way or the other... others are just gay or not.

    many evidences point towards genetic: studies of twins separated at birth (if one twin is gay, the chance of the other one being gay is too great to be left to chance); the more men a mother gives birth to, the higher the chance of the youngest being gay, regardless of them growing up together or not, etc.

    but there is also plenty evidence pointing towards non-genetic causes.

    the study of animals is tricky because very few animals have sex for pleasure! (dolphins do if I remember) ... so we have to look at either those animals, or animals who chose life partners (I know there are examples of male-male partners, like in penguins). -- a dog humping your leg is not evidence for either side!

    the argument that homosexuality is a choice is stupid at best, dangerous at it's worst. how many lives have been ruined because people can't understand why they just can't change? -- if gayness was a choice, why would anyone put themselves through that in places where it is not acceptable.

    homosexuality is a choice? here's a simple thought experiment for us straight males: imagine yourself having sex with Brad Pitt... I personally don't think I'd enjoy that too much. And i don't see why, for the life of me, I'd want to stop finding sex with women enjoyable.

    ... if it's so clear to you that it's a choice, please explain why anyone would wake up one morning and say "I think I'll be gay today. I think I want to be looked down upon, bullied, and possibly lose friends and family. I think from now on I want to not enjoy sex with women, I want to enjoy sex with men."

    also, I don't see homosexuality, and the rise of it, as a mistake or disease. homosexuality can serve many purposes -- I see one very important purpose:

    - raising children who have no parents, and not giving birth to more unwanted children.
    Last edited: Mar 20, 2007
  23. Mar 20, 2007 #22


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    I really think there is enough evidence to show it has a biological basis , not necessarily purely genetic based as moe already stated. To isolate a gene for homosexuality or say it has is probably as fallacious as isolating a gene for intelligence, or schizophrenia, etc, where there probably is not one singular gene that affects such complex biological/social behavior. Of course it is not to say psycological variables don't also play a role in such a complex psycosocial biological behavior either.

    Most physicians ( who are privey to such personal histories ) will tell you most homosexuals knew they were homosexual at a very young age, many prepubescently.

    With that said, is there a genetic predispostion or some other physical factor that influences homosexuality?

    However, nature has provided us with a wonderful natural experiment called congenital adrenal hyperplasia where these women (depending on the study, have almost 60% ( from 5-35% to 60 depending on the study) homosexuality rate.) These women produce high testosterone while in the womb due to a enzyme defect in their adrenal glands and sometimes long after birth if not detected in time. Usually it is easily corrected with medicines..

    http://www.boskydell.com/political/outlooks.htm [Broken]


    general lecture in reproductive medicine on
    CAH http://home.epix.net/~tcannon1/Physioweek9.htm

    Thus, it shows that the hormonal environment of the fetus may affect the sexual identity of a person. Thus, could homosexuality may be an acquired biological phenomenom rather then a genetic phenomenom? We don't have such a natural experiment in men with the exception of something called complete androgen insensitivity syndrome where these are genetic males born with completely perfect external female genitalia and breast and develop into attractive females who can't reproduce of course. Many go on to marry men. (technically they are gay?...genetic males having sexuall relationships with males.) However, it really isn't fair because their male hormones don't work at all (because they lack all testosterone receptors) and only their estrogen receptors get activated.

    Can't find it but I remember something about some ground breaking work with the BSTc in the hypothalamus at the Institute for Brain Research in Amsterdam, Netherlands by Dr. Zhou et al, and also by Dr. Wilson Chung et al in the usa.

    Besides, aren't we getting away from purely genetics as the only determinant of physical/psycological traits? I think we are considering the epigenetic material may be just as important in determing traits and these are easily susceptible to environmental damages? I think they are looking into this as a cause of something like bipolar I disease which clearly has a biological basis but in identical twins only 50% ( rather than the 100%) rate of both having the disease. They are looking into the epigenetic material that is altered by the environment in one vs the other.

    I really don't think the answer is clear either way and both sides should avoid dogmantic statements ie: It is completely a choice or completely genetic or biologically based. I think homosexuality is too complex to pigeon hole each person into one or the other.
    Last edited by a moderator: May 2, 2017
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